It was the unwavering custom of Pietro Cubbiddu, patriarch of Tuscany's Villa Antica wine empire, to take a solitary month-long sabbatical at the end of the early grape harvest, leaving the winery in the trusted hands of his three sons. His wife, Nola, would drive him to an isolated mountain cabin in the Apennines and return for him a month later, bringing him back to his family and business.

So it went for almost a decade - until the year came when neither of them returned. Months later, a hiker in the Apennines stumbles on their skeletal remains. The carabinieri investigate and release their findings: they are dealing with a murder-suicide. The evidence makes it clear that Pietro Cubbiddu shot and killed his wife and then himself. The likely motive: his discovery that Nola had been having an affair.

Not long afterwards, Gideon Oliver and his wife, Julie, are in Tuscany visiting their friends, the Cubbiddu offspring. The renowned Skeleton Detective is asked to reexamine the bones. When he does, he reluctantly concludes that the carabinieri, competent though they may be, have gotten almost everything wrong. Whatever it was that happened in the mountains, a murder-suicide it was not.

Soon Gideon finds himself in a morass of family antipathies, conflicts, and mistrust, to say nothing of the local carabinieri's resentment. And when yet another Cubbiddu relation meets an unlikely end, it becomes bone-chillingly clear that the killer is far from finished...